Screw-compressor



July 28, 1959 SHOZO SHIOKAWA 2,

SCREW-COMPRESSOR Filed March 24. 1955 Y 7 Sheets-Sheet 1 INVENTOR SHOZO SHIOKA WA ATTORNEYS July 28, 1959 SHOZO SHIOKAWA 2,896,529

SCREW-COMPRESSOR Filed March 24, 1955 7 Sheets-Sheet 3 INVENTOR SHOZO SH'IOKA WA ATTORNEYS July 28, 1959 9-1020 s lo w 2,896,529

SCREW-COMPRESSOR Filed March 24, 1955 V 7 Sheets-Sheet 4 INVENTOR SH 020 SHIOKAWA BYWMI @WM AT TORNE YS July 28, 1959 SHOZO SHIOKAWA 2,396,529

SCREW-COMPRESSOR Filed March 24, 1955 'TSheets-Sheet 5 INVENTOR SHOZO SHIOKAWA M4 mad ATTORNEYS Filed March 24, 1955 July 28, 1959 51-1020 sH o w 2,895,529

SCREW-COMPRESSOR 7 Sheets-Sheet 6 SHOZ .O SHIOKA WA %MLML. W

ATTORNEYS July 28, 1959 sHozo SHIOKAWA 2,896,529

SCREW-COMPRESSOR Filed March 24, 1955 7 Sheets-Sheet '7 mvzuron snozo SHIOKA WA QZMML, mww

ATTORNEYS United States Pate SCREW-COMPRESSOR Shozo Shiokawa', Toyonaka City, Japan Application March. 24, 1955, Serial No. 496,537 Claims priority, application Japan April 10, 1954 6 Claims. (Cl. 100-490) This invention relates to a press, and more particularly a press which has a long compression stroke, yet is operable with little stress on the working parts thereof.

Heretofore in'presses in which large compressive forces are to be exerted, it has been necessary to make the operating parts for applying the compressiveforces of sufficient strength to transmit. these forces directly or indirectly to the material being pressed. Alternatively, if a large mechanical advantage is to be secured, the stroke of the press has been made correspondingly short;

An object of the present invention is to overcome these drawbacks, and to provide a press which can apply large compressive forces to the material being pressed through operating parts which do not need to be sufficiently strong to withstand the full amount of these forces.

Other and further objects of the invention will become apparent from the following specification, claims, taken together with the accompanying drawings in which:

Fig. 1 is a front elevation View of a press according to the invention;

Fig. 2 is a side elevationvof the press according to Fig. 1, partially in section and with sprocket chains omitted;

Fig. 3 is an elevation section taken on line 33 of Fig. l;

Fig. 4 is a section taken on line 4-4 of Fig. 1;

Fig. 5 is asection on line 5-5 of Fig. 3;

Fig. 6 is a side elevation of a modificationof a press according to the invention;

Fig. 7 is a cross section on line 7-7 of Fig. 6; and

Fig; Sis a cross section on line 8--8 of Fig.7.

The press consists of four generally vertical threaded shafts 2 which have on the upper ends thereof an upper load engaging member 1 through which each of the threaded shafts extends. Nuts 2a prevent the load engaging member 1 fromslidinlg upwardly beyond the ends of the threaded shafts 2'. The shafts extend downwardly through abase b, and each of them has threaded thereon an upper sprocket wheel 5 and a lower sprocket wheel 6. Immediately above the upper sprocket wheels 5 is a lower load supporting member 3 having bores 3a therein through which each of the threaded shafts 2 extend. Between lower sprocket wheels 6 and the base b is a supporting frame a. Immediately above lower sprocket wheels 6 is a bearing plate 4 having a plurality of Ibores 4a therein through which threaded shafts 2 extend. Above the bearing plate 4 is a crankshaft bearing 28 through which extends a crankshaft 25 having a large gear 24 on the end thereof. The crankshaft bearing 28- is secured to base b by bolt 0, and clamps bearing plate 4 and frame a between it and base b.

Eccentrically secured to the crankshaft 25 is a thrust plate 26 which bears against the under surface of lower load supporting member 3. Between two of the threaded shafts 2 is a vertically disposed? clutch assemblywhich ICC 2. extends between the lower load supporting member 3 and the base ,b. This clutch assembly comprises a shaft 12 which is journaled at its upper end in. the lower load supporting member 3 and at its lower end in the base b. Keyed thereto are lower and upper conical clutch cones 9' and 10.1. Upper clutch cone 10. is urged downwardly by a springg held on the shaftby. a retaining ring h. Immediately beneath. upper clutch. cone Ill is a sprocket wheel 7 slidable onshaft 12, the central portion of which sprocket wheel has a conical recess therein adapted to receive the upperclutch cone .10. Around the lower portion of the shaft immediately above. thelower, clutch cone 9 is a sprocket wheel 8, the central portion of which.

likewise has a conical recess therein adapted to receive mounted between the sprocket wheels 7 and 8. Around the lowerend of shaft 12is abevel gear 13- which meshes with a bevel gear 14 mounted on a horizontal transverse shaft 15; The shaft 15 is mounted in bearing supports 15a on the base b and extends beneath the bearing plate 4- outside of the periphery thereof. The end of the shaft carriesa large bevel gear 16, which in turn is meshed With a pair of bevel gears 18 and 19 slidably mounted on a shaft 22 extending generally parallel to the crankshaft 25 and mounted in bearing supports 22a on the base. b. One end ofshaft 22 has a small gear 23 thereon which is in mesh with large gear 24, and the opposite end of shaft 22 has a pulley 27 thereon. Brackets. k carry a slide i on whichis slidably mounted handle 21. A two sided clutch 20 keyed to shaft 22 for rotation therewith is attached to handle 21 by fork 17 and is engageable with either bevel gear 18 or 19.

A sprocket chain d connects the upper sprocket wheels 5 and the sprocket wheel 7 on the clutch assembly, while a sprocket chain e connects the lower sprocket Wheels 6 and the sprocket Wheel 8 on the clutch assembly.

In the operation of the device, the large gear 24 is.

member 3, the crankshaft 25 is permitted to rotate until.

the thrust plate 26 reaches the upper limit of its vertical movement, at which point the lower load supporting.

member 3 has been lifted from the sprocket Wheels 5.

The operation of the clutch assembly is then commenced by sliding the handle 21 :and thus the clutch 20 into engagement with the bevel gear .18 or 19 which will drive the shaft 12 in the proper direction to rotate the lower and upper sprocket wheels 7 and 8 for moving the threaded shafts 2 downwardly relative to said sprocket wheels. With thematerial to be compressed placed be tween the upper load. engaging member 1 and the lower load supporting member 3, theupper thrust of thrust plate 2.6 will be-transmitted through the material being compressed to upper load engagingmember 1 and will urge the threaded shafts 2 upwardly. This will draw lower sprocket wheels '6 against the bearing plate 4 locking themagainst rotation. Lower clutch cone 9 will revolve within the conical depression in sprocketwheel 8 without transmitting motion to the. sprocket wheel which will be suflicientto overcome the locking action of the sprocket wheels 6 against the bearing plate 4. The lower load supporting member, however, will be compressed against the. material being compressed and will free upper sprocket wheels 5 for rotation around threaded shafts 2. Spring g will urge upper clutch cone 10 into engagement with sprocket wheel 7, and will cause the upper sprocket wheels 51o rotate to move upwardly along thepast the point at which the upper thrust is greatest, i.e. with the thrust plate 26 in the vertical position, the upper sprocket wheels 5 will be against the lower load supporting member 3, thus locking them against further rotation.

When the thrust plate 26 moves downwardly, the sprocket wheels 6 will no longer be locked tightly against the bearing plate 4, and the lower clutch cone 9 will once more revolve the sprocket wheel 8 thus rotating the sprocket wheels 6. This rotation will draw the threaded shafts 2 downwardly together with the upper load engaging member 1, the lower load supporting member 3, the sprocket wheels 5 and the material to be compressed. The only weight which will be supported during the descent of these parts is that of those parts. The descent will continue until sprocket wheels 5 have reached the point at which their upward movement commenced, i.e. sprocket wheels 7 and 8 are against bearing 11. At this point, handle 21 is moved to disengage the bevel gears from the shaft 22, and the rotation of the clutch assembly ceases.

This operation is repeated a sufi'ic-ient number of times to achieve the desired compression, the only parts having to receive and transmit the compressive load being the crankshaft 25, the thrust plate 26 and the load engaging and supporting members 1 and 3. The operation can be repeated a sufficient number of times to achieve the desired compressive stroke, the length of the stroke being limited only by the length of the threaded shafts 2.

The modification \of the device shown in Figs. 6-8 is basically the same as the form shown in Figs. 1-5. The position of the lower load supporting member and the bearing plate have been reversed, however. There is provided the four threaded shafts 2', and the upper load engaging member 1, as well as the base b carrying the shaft 22 and the bevel gearing 18', 19' with the clutch member 20 and handle 21. A bevel gear 16' is provided which is used to drive the clutch assembly through shaft .15 in the same manner as in the form of the invention shown in Figs. 1-5.

However, there is provided a crankshaft bearing 35 which extends upwardly from the base b, and is extended to form the lower load supporting member 2h. Bores 29a are provided through which the threaded shafts 2' extend. Crankshaft 25 extends through the crankshaft bearing and has eccentrically mounted thereon thrust members 31 and 31. Beneath the .lower supporting member 29 on the threaded shafts 2' are threaded the upper sprocket wheels 5 connected by the sprocket chain d, and immediatelyabove the base b on the threaded shafts 2' are threaded the lower sprocket wheels 6' connected by the sprocket chain e. A clutch assembly is provided which is identical with the clutch assembly in the form of the invention shown in Figs. 1-5. Between the upper and lower sprocket wheels 5' and 6' are mount- .e d two bearing members 30 and 30 having bores therein through which threaded shafts 2 extend, and which are contacted by the thrust members 26. v

The operation of this modification of the device is very similar to that of the form shown in Figs. 1-5. The crankshaft 25 is permitted to rotate until the thrust members 26' reach the lowest point in their vertical reciprocation. At this point, the vertical thrust is transmitted through the bearing members 30 and 30' to sprocket wheels 6, threaded shafts 2 and upper load engaging member 1 to the material being compressed. The bearing members 30 and 3%, press against sprocket wheels 6' thus locking them against rotation. The clutch assembly then permits sprocket wheels 5 to rotate and move up wardly against the bottom of the lower load supporting member 29. When the thrust members 26 begin to move upwardly, the sprocket wheels 6' are free to rotateand the bearing members 30 and 30 are lifted. When the thrust members 26 and 26' again start their downward movement, the cycle is repeated. Handle 21' must be operated in the same manner as with the form of the invention shown in Figs. 1-5 in order to start and stop the clutch assembly at the proper times.

In both modifications of the device, when the handle 21 is moved to actuate the bevel gear which will rotate the clutch assembly in the direction to move the threaded shafts 2 upwardly in relation to the sprocket wheels 5 and 6, the threaded shafts with the upper engaging member 1 thereon can move upwardly in a continuous movement. This is true because both the upper and lower sprocket wheels are not blocked by contact with either the lower load supporting member or the thrust plate, and consequently the clutch assembly will cause both the upper sprocket wheels and the lower sprocket wheels to act simultaneously.

It has also been found to be desirable to provide means for preventing the sprocket wheels from running upwardly on the threaded shafts and becoming jammed against the bearing plate or the lower load supporting member so that they do not start operating freely when the clutch assembly again becomes engaged. This is accomplished by providing an extension on the upper sprocket wheel 7 and the lower sprocket wheel 8 in the clutch assembly. This is clearly shown in Fig. 3. These extensions do not extend over the full half circumference of the sprocket wheel, but are reduced to provide a clearance equal to the angle j as shown in Fig. 5. Thus, when one of the groups of sprocket wheels encounters an obstacle, the other group is stopped after the sprocket wheel in the clutch assembly which drives the sprocket Wheels has rotated through an angle j.

It is thought that the invention and its advantages will be understood from the foregoing description and it is apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing its material advantages, the forms hereinbefore described and illustrated in the drawings being merely preferred embodiments thereof.

I claim:

1. A press comprising in combination an upper load engaging member, a plurality of threaded shafts depending therefrom, a base through which said shafts extend, bearing means between said shafts above said base, rotatable means threaded on each of said shafts and connected to each other for simultaneous rotation, said r0- tatable means being between said base and said bearing means, a lower load supporting member through which said shafts pass, further rotatable means threaded on each of said shafts and connected to each other for simultaneous rotation, said further rotatable means being between said bearing means and said lower load supporting means, a clutch assembly mounted between said base and said lower load supporting means and engaged with said rotatable means threaded on each of the shafts between the base and the bearing means and with said further rotatable means between the bearing means and the lower load supporting means, a driving shaft on said base, clutch means for intermittently connecting said driving shaft to said clutch assembly, a crankshaft mounted on said base, thrust means eccentrically mounted on said crankshaft for exerting a thrust between said lower load supporting means and said bearing means through a material being pressed, said threaded shafts and said rotatable means threaded on said shafts between said base and said bearing means, and gearing means connecting said crankshaft and said driving shaft.

2. A press comprising in combination an upper load engaging member, a plurality of threaded shafts depending therefrom, a base through which said shafts extend, bearing means between said shafts above said base, a lower sprocket wheel threaded on each of said shafts between said base and said bearing means, a lower sprocket chain Connecting the lower sprocket wheels, a lower load supporting member above said bearing means through which said shafts pass, an upper sprocket wheel threaded on each of said shafts between said bearing means and said lower load supporting means, an upper sprocket chain connecting the upper sprocket wheels, a clutch assembly mounted between the base and the lower load supporting means having upper and lower sprocket wheels engaging said upper and lower sprocket chains, a driving shaft on said base, clutch means for intermittently connecting said driving shaft with said clutch assembly, a crankshaft mounted on said base, thrust means eccentrically mounted on said crankshaft for exerting a thrust between said lower load supporting member and said bearing means through a material being pressed, said threaded shafts and said lower sprocket wheels, and gearing means connecting said crankshaft and said driving shaft.

3. A press comprising in combination an upper load engaging member, a plurality of threaded shafts depending therefrom, a base through which said shafts extend, bearing means between said shafts above said base, a lower sprocket wheel threaded on each of said shafts between said base and said bearing means, a lower sprocket chain connecting the lower sprocket wheels, a lower load supporting member above said bearing means through which said shafts pass, an upper sprocket wheel threaded on each of said shafts between said bearing means and said lower load supporting means, an upper sprocket chain connecting the upper sprocket wheels, a clutch assembly mounted between the base and the lower load supporting means having upper and lower sprocket wheels engaging said upper and lower sprocket chains, a driving shaft on said base, clutch means for intermittently connecting said driving shaft with said clutch assembly, a crankshaft mounted on said base, a thrust member eccentrically mounted on said crankshaft for exerting a thrust against said lower load supporting member, thereby drawing said lower sprocket wheels against said bearing means through a material being pressed and said threaded shafts, and gearing means connecting said crankshaft and said driving shaft.

4. A press comprising in combination an upper load engaging member, a plurality of threaded shafts depending therefrom, a base through which said shafts extend, bearing means between said shafts above said base, a lower sprocket wheel threaded on each of said shafts between said base and said bearing means, a lower sprocket chain connecting the lower sprocket wheels, a lower load supporting member above said bearing means through which said shafts pass, an upper sprocket wheel threaded on each of said shafts between said bearing means and said lower load supporting means, an upper sprocket chain connecting the upper sprocket wheels, a clutch assembly mounted between the base and the lower load supporting means having upper and lower sprocket wheels engaging said upper and lower sprocket chains, a driving shaft on said base, clutch means for intermittently connecting said driving shaft with said clutch assembly, a crankshaft mounted on said base, a thrust member eccentrically mounted on said crankshaft for exerting a thrust against said bearing means, thereby forcing said bearing means against said lower sprocket wheels and exerting compression on the material being pressed through the sprocket wheels and the threaded shafts, and gearing means con necting said crankshaft and said driving shaft.

5. A press comprising in combination an upper load en gaging member, a plurality of threaded shafts depending therefrom, a base through which said shafts extend, bearing means on said base extending upwardly between said shafts, a lower sprocket wheel threaded on each of said shafts between said base and said bearing means, a lower sprocket chain connecting the lower sprocket wheels, a lower load supporting member above said bearing means through which said shafts pass, an upper sprocket wheel threaded on each of said shafts between said bearing means and said lower load supporting means, an upper sprocket chain connecting said upper sprocket wheels, a clutch assembly mounted between said base and said lower load supporting means comprising upper and lower sprocket wheels engaged with said upper and lower sprocket chains, upper and lower clutch cones frictionally engageable with said upper and lower sprocket wheels, and a shaft on which said upper and lower clutch cones are slidably mounted, a driving shaft on said base, clutch means for intermittently connecting said driving shaft to the shaft in said clutch assembly, a crankshaft mounted on said base above said bearing means, a thrust member eccentrically mounted on said crankshaft for exerting a thrust against said lower load supporting member, thereby drawing said lower sprocket wheels against said bearing means through a material being pressed, said threaded shafts and said lower sprocket wheels, and gearing means connecting said crankshaft and said driving shaft.

6. A press comprising in combination an upper load engaging member, a plurality of threaded shafts depending therefrom, a base through which said shafts extend, hearing means between said shafts above said base, and through which said threaded shafts pass, a lower sprocket wheel threaded on each of said shafts between said base and said bearing means, a lower sprocket chain connecting the lower sprocket wheels, a lower load supporting member mounted on said base above said bearing means and through which said shafts pass, an upper sprocket wheel threaded on each of said shafts between said bearing means and said lower load supporting member, an upper sprocket chain connecting the upper sprocket wheels, a clutch assembly mounted between said base and said lower load supporting means comprising upper and lower sprocket wheels engaged with said upper and lower sprocket chains, upper and lower clutch cones engageable with said upper and lower sprocket wheels, and a shaft on which said upper and lower clutch cones are slidably mounted, a driving shaft on said base, clutch means for intermittently connecting said driving shaft to the shaft in said clutch assembly, a crankshaft mounted on said base between said lower load supporting member and said bearing means, a thrust member eccentrically mounted on said crankshaft for exerting a thrust against said bearing means, thereby forcing said bearing means against said lower sprocket wheels for exerting a compression on a material being compressed through said lower sprocket wheels and said threaded shafts, and gearing means connecting said crankshaft and said driving shaft.

References Cited in the file of this patent UNITED STATES PATENTS 164,608 Tappey et al June 15, 1875 1,774,245 Strout Aug. 26, 1930 2,301,943 Georg Nov. 17, 1942 FOREIGN PATENTS 293,028 Germany July 12, 1916 879,087 Germany June 11, 1953 

